Environment and Planning B: Urban Analytics and City Science

Based on the Census for Transportation Planning Package (CTPP) 1990, in this paper I will attempt to explain intraurban variations of commuting time and distance in Columbus, OH. Whereas commuting times are directly available from the CTPP, commuting distances are recovered by GIS network techniques as the shortest-time distances through the urban road network. Explanations of commuting are first attempted by measures of job proximity such as distances from employment centers and a gravity-based index accounting for job competition among workers. The influence of employment centers on commuting sheds new light on polycentric urban models. The variation of commuting distance is well explained by the gravity-based job proximity index. That is to say, how far people commute is explainable to a large extent by urban land use. However, how much time people spend on commuting is complicated by their socioeconomic status, which affects their choice of commuting modes. Finally the research demonstrates the promise of explaining commuting times by workers' characteristics such as percentage of black workers, female labor participation ratio, percentage of multiple-worker households, home-ownership status, educational attainment, and wage rate. In the analyses, spatially lagged dependent variables are introduced to control for the effect of spatial autocorrelation.

The evidence for the influence of urban configuration on outdoor climate conditions, on the energy balance of buildings, and on diffusion of pollutants is quite conclusive. But the exact characterization of this complex link remains critical, especially because of the extreme morphological heterogeneity at a fine granularity level: the building and its close environment. In this approach I try to cope with this difficulty, by working at the district or city scale, by assimilating the urban fabric into a porous medium with a rigid solid skeleton, and by proposing a simple spatial model based on a set of original morphological indicators of environmental performance: density, rugosity, porosity, sinuosity, occlusivity, compacity, contiguity, solar admittance, and mineralization. This system of indicators has been embedded in a shell of development of GIS and applied to various urban fabrics. The possible applications of this model are diverse: simplified analysis of outdoor microclimate tendencies, sustained environmental evaluation of a neighborhood, interdistrict or intercity comparisons, or modelling of the climate effect on future urban amenities.

In this paper I assess the current state of knowledge about quality-of-place (QOP) analysis. I find that there are persistent problems in measuring QOP, highly personal links between individual QOP perceptions and aggregate QOP measurements, mostly unintended impacts of public policy decisions on QOP outcomes, and inadequate triangulation across model approximations and data limitations when building tools to support local decision-making. The analytical community should therefore acknowledge that people hold diverse preferences, increase efforts to detect and model the consequences of policies, look across levels of decision-making for influences on QOP, and build adaptive analytical capacity.

Theories about communicative planning have forcefully emphasised how language and modes of communication play a key role in shaping planning practice, public dialogues, policymaking, and processes of collaboration. These days, however, discussions on planning seem to reestablish an old philosophical confrontation between Jürgen Habermas's plea for a discoursive ethic and Michel Foucault's thesis of the omnipresence of discoursive powers. Some—mostly overlooked—central themes to this controversy are the epistemological and ontological conditions of Habermas's theory of communicative action. Furthermore, theories of communicative and collaborative planning are criticised because they do not deal with questions on government and governmentality when the power of institutional discourses and the planning of legal decisional structures are discussed. In this paper, I will exemplify the controversy between the Habermasian (the ethics of participation and democratic communication) and the Foucaultian (the art of governance) planning theories, by comparing public participation in Norway with experiments on citizen involvement in Denmark.

If the size of a space is measured by counting the number of places available for a particular activity, rather than by using an absolute measure such as the square metre, then small people may find the world larger. Size measured by number of places becomes a function of the size of the user, and the form of this function suggests that the everyday environment has a fractal dimension, a single number which may be associated with architectural qualities. This measure was tested with an experiment based on children playing hide and seek and was used to explain some illusions of perception of size.

There has been considerable interest in recent decades in the identification of the physical correlates of crime in different urban settings. In this study we focus on bus stop crime and seek to understand how different environmental attributes in the vicinity of a bus stop can affect the incidence of crime. We first review evidence from the relevant literature to understand the impacts of built environment on crime. This is followed by the presentation of our empirical research. We have used a stratified random sample of sixty bus stops in downtown Los Angeles to examine the effects of environmental and land-use attributes on crime rates. Using descriptive statistics, correlations, regression and discriminant analyses, and matched-pair analysis, we find some relations between the existence or absence of certain environmental attributes and the incidence of crime.

A radiosity model has been developed for calculating the sound distribution in urban streets with diffusely reflecting boundaries. In this paper I present the results of a parametric study by using the computer model. A typical urban element consisting of a major street and two side streets is analysed. The analysis is focused on the characteristics of sound pressure level and reverberation time in the urban element, as well as the effectiveness of the boundary treatments and street arrangements for noise reduction.

By using a modified Cheung model of price control, we show that discriminatory zoning is economically an inefficient protectionist alternative to nondiscriminatory zoning. The exclusionary zoning on the Peak of Hong Kong arose in order to give Europeans a housing area free from economic price competition with the Chinese. Documentary evidence is adduced to support this view of the law. Such zoning collapsed after the Second World War when European owners needed to realize their capital. Land-transaction records of certain sites on the Peak are analysed to support this interpretation. Without claiming to offer an exclusive explanation as to the formation of discriminatory law, we advance the case that discrimination is economically inefficient and will be abolished once the favoured group ceases to benefit from its continuation.